All block-inserting routines on the this model will insert the block on the given position, or if this is not provided, on the current position. After inserting the blocks, the current position will be updated.

In addition, the newly inserted block(s) might be merged with blodcks at the current position.

Adds an end-block. If no parameter is given, uses the current position, otherwise appends the end block to the given $block. See also current_block. Will also update the position of last_block to point to the newly added block, and return this block.

Adds a joint (an unlabeled, star-shaped node) to the flowchart and then connects each block in the given list to that joint. This is used f.i. by if-then-else constructs that need a common joint where all the branches join together again.

When adding a block right after a joint, they will be merged together and the joint will be effectively replaced by the block.